ΔE 8.6, close: similar, with a visible difference side by side. Old Wood is a little darker, more saturated, warmer than IDF Gray 2 (-1981 Golan).
Usually, if you are not matching paint already on the model. Close match (ΔE 9). Old Wood is a little darker, more saturated, warmer than IDF Gray 2 (-1981 Golan).
The same difference applies the other way round: IDF Gray 2 (-1981 Golan) is a little lighter, more muted, cooler.
ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.
See IDF Gray 2 (-1981 Golan) on the colour wheel See Old Wood on the colour wheel
All matches: IDF Gray 2 (-1981 Golan) equivalents · Old Wood equivalents